A fluid valve such as usable in a household plumbing system typically has a housing with an inlet and an outlet, and a valve body is fed so as to move longitudinally within the housing. In practice, such fluid valves are used for varying a flow cross section of a fluid passage.
The present invention specifically relates to a fluid valve whose flow cross section is reduced in a throttle or flow-impeding position, so that on flow through the valve a pressure drop results between the inlet and the outlet. As a result, a pressure differential is present between the inlet and the outlet and the amount of liquid flowing through the fluid valve is limited.
Consequently, within the context of the invention, the term pressure differential between the inlet and the outlet refers to a higher pressure at the inlet than at the outlet.
The fluid valve may be provided as a component of a plumbing system for producing bubbles. There, for example a bathwater circulating system is provided that includes a pump, an air-supply conduit that is provided with an intake throttle and that opens into a water-supply conduit that is connected to the intake port of the pump, and a fluid valve connected to the output port of the pump, the fluid valve being used in the described arrangement as a pressure-reducing valve.
The microbubbles produced by the bathwater circulating system are very fine and are similar in their structure to a mist or very fine foam. On the skin of a user, a vitalizing effect is achieved, and at the same time a particularly gentle and pleasant tingling can be felt.
The functioning mode of the bathwater circulating system is based on the fact that under application of pressure, ambient air or another gas is dissolved in the bathwater, and subsequently, as a result of depressurization, minute microbubbles form in the air/water mixture.
A bathwater circulating system with the features as described above is known from JP 2008-290050. In this system, bathwater is drawn from a filled bathtub through a pump and is mixed with ambient air upstream of the pump. Superatmospheric pressure is applied to the air/water mixture by the pump, as a result of which part of the ambient air dissolves in the bathwater.
The mixture is then passed into a fluid settling chamber in which any excess ambient air in the form of residual large bubbles in the mixture are separated from the liquid. As a result of the separation of the liquid phase from the gaseous phase, the bathwater extracted from the fluid settling chamber holds only ambient air in a dissolved form. The bathwater with the ambient air dissolved therein is then passed to a throttle unit with nozzle-shaped constrictions, and as a result of the pressure drop on the throttle device, the ambient air previously dissolved in the bathwater in the form of very fine bubbles, which are also referred to as microbubbles, is released.
A bathwater circulating system is known from U.S. Pat. Nos. 8,579,266, 8,720,867, and 9,060,916 (EP 2 226 056, EP 2 226 057, and EP 2 703 071) in which bathwater is drawn by a pump, and a gas, in particular ambient air, is supplied only after pressure has been applied onto the bathwater using the pump. The air/water mixture thus formed is passed to a fluid settling chamber for separating any excess ambient air.
A similar arrangement is described in WO 2007/051260, and the bathwater is enriched with ozone.
According to DE 20 2011 110 581, bathwater is enriched with CO2 that is held in a gas container, and a compensation tank is provided downstream of a pump.
When using the fluid valve as a pressure-reducing valve in a plumbing system, there is a risk that the fluid valve becomes clogged up with impurities and will become impaired in its function thereby. A similar risk of clogging with impurities is present also in other applications.